DRILLHOLE MEASUREMENTS: Survey tool cuts drillstring trip-out times
Stockholm Precision Tools (SPT) has launched the latest generation of its north-seeking gyroscopic survey tool for the oil and gas and mining sectors. The SPT 007-42 MIG provides improved measurement accuracy and user-friendliness, according to general manager Orlando René Ramirez.
Stockholm Precision Tools capped a successful OTC by taking the Swedish Trade Council’s Achievement Award 2006. Pictured is general manager Orlando Rene, receiving the award from STC’s marine and offshore manager Göran Hamne.
The battery-powered tool is an inclinometer designed for gyroscopic and magneto metric measurements in boreholes and wells, such as constituent azimuth, dip angle and tool face. It comprises a gyroscopic module and a telemetric module; a driver with a central processor and memory module; and an accumulator cell module (battery).
The tool’s modular construction allows measurement using the gyroscopic module in both cased wells and wells with great geomagnetic anomalies, as well as geomagnetic azimuth in wells with a homogeneous magnetic field. It can therefore be used down holes which are being drilled with magnetic drill-pipe, saving the operator the time and cost involved in tripping out the drill-string ahead of performing a survey.
Competing devices can take measurements in the presence of magnetic drill-pipe. However, they cost substantially more, or need to take drift checks, which is unnecessary with the SPT tool.
“Our tool measures directly the earth’s rotation, finding the geographical true north,” Ramirez says. “This makes it more accurate than alternative tools which are based on indirect measurement methods.” The SPT system is claimed to be accurate to ±1° in azimuth, with a repeatability of 0.5° in azimuth.
Having input the depth and latitude into the software program, the tool uses this data to calculate azimuth in relation to true north. It also gives the inclination, which is sufficient to calculate its location. There is no need to calibrate the tool, or to find a reference point facing true north or magnetic north on the well’s surface location, prior to the start of surveying.
Processing software integrated into the tool allow locations to be provided in real-time while it is down-hole. The focus is on maximizing information so that detailed reports can be presented to the client.
Another advantage of the SPT tool is its compact size. It measures 42mm in diameter and 2.6 m in length, including the cable-head, compared with a typical length of 8m for competitors’ tools.
SPT claims a new operator can learn to use the tool within a week. It is currently being deployed by American Canadian, Australian and Swedish drilling contractors in applications around the world.
For more information contact Orlando René Ramirez, Stockholm Precision Tools. Tel: +46 85 907 33 10, fax +46 70323 2528,[email protected], www.stockholmprecisiontool.com.
